Grate bar structure for sintering machines



Jan. 12, 1932.

T. H. BENNETT GRATE BAR STRUCTURE FOR SINTERING MACHINES Filed Feb. 1, 1930 I r 4 m :2;

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Patented Jan. 12, 1932 UNITED STATES PATENT OFFICE Y THOMAS I. BENNETT, OF LA s'ALLE, ILLINOIS, ASSIGNOR TO MATTHIESSEN & HEGELEB zINo 00., or LA SALLE, ILLINOIS, A CORPORATION OF ILLINOIS GRATE BAR STRUCTURE FOR SINTERING MACHINES Application filed February 1, 1930. Serial No. 425,083.

I) invention relates generally to sintering machines and has to do particularly with the grate bars supported by the pallets or sintering pans and the manner of mounting such grate bars upon the pallets or pans.

The grate bars heretofore employed with the pallets or sintering pans of sintering machines of the well-known Dwight & Lloyd type have each been formed of one comparatively long piece extending from one side to the other of the pallet, with the opposite ends supported upon the opposite sides of the pallet. These former grate bars are objectionabIe-fOr the following, among other, reasons: 1 they tend to warp out of shape quickly requiring replacement of the entire grate bar; they develop cracks resulting in breakage after a few days use with considerable loss which makes the sintering process and the maintenance of the machine quite expensive; and breakage of the grate atany'point requires replacement of the entire grate bar unit.

The main object of my invention is to providean improved grate bar structure for sintering machines wherein the foregoing objectionable features have been practically eliminated. More particularly, my invention provides a grate bar which is formed of two end-wise disposed, comparatively lightweight half-grate bar sections each of which is independently supported by the pallet or pan and each of which is so formed and sup ported that the grate bar may be used a comparatively long time without breakage due to cracks, warping is reduced to the minimum, if not entirely eliminated, so that over long periods of operation practically no replacement is necessary due to this cause, in case of warping, cracking or breaking the affected section only need be replaced, and upkeep and replacement costs are materially reduced.

Another object is to provide a novel form of half-grate bar section having provision for self-holding the same in a predetermined position upon the pallet and to prevent vertical and lateral'displacement of the same with respect to the pallet. I

A more specific object is to provide a grate bar section adapted to extend approximately half-way across the width of the pallet or sintering pan and having a jaw formation at its inner end for interlocking enga ement with a mid-portion of the pallet and aving adjacent its inner end lugs which cooperate with the pallet for preventing lateral displacement of the grate bar section.

Other objects and advantages will become apparent as'this description progresses and by reference to the drawings wherein,

Figure 1 is a top plan view of a pallet and grate bar assembly embodying my invention;

Fig. 2 is a section through one of the grate lli ar units taken substantially on line 2-2 of Fig. 3 is a transverse section taken substantially on line 33 of Fig. 1;

Fig.4 is a side elevational view of one of the grate bar sections; and

, Fig. 5 is a left end view of the section shown in Fig; 4.

In the drawings, I have illustrated my invention as applied to a pallet or sintering pan which is of a construction well adapted for use with sintering machines of the wellknown Dwight & Lloydtype. In machines of this character a plurality of pallets are mounted to follow in an endless path of travel, the pallets forming a substantially continuous series so that each pallet in operative position is located closely adjacent to the next leading and following pallets of the series, as, for example, shown in the application filed by Oscar Gerlach Serial No. 243,840, filed December 31, 1927, for Process and apparatus for purifying zinc. It will be understood, however, that although my invention is well adapted to the above form of machine, it is not necessarily limited thereto and may be used in other similar instances where the same or equivalent conditions of operations are to be met. f

I It will be further understood that wherever I refer herein to pallet I intend to include the sintering pan or bed structure which supports the grate bar units.

In the drawings, the pallet 10 consists of side walls 11 connected at their ends by transverse end bars 12. These side walls 11 are also connected or bridged by uniformly spaced intermediate transverse bars 13, forming a sturdy bed or frame for supporting the grate bar units. The outer or transverse end bars 12 and the adjacent intermediate bars 13, as well as the intermediate bars themselves, are bridged at their-center by U- port bars cooperating with such end bars are complementally tapered to provide a wedgesupport as between thetransverse end bars 12 and the support bars carried thereby to add rigidity and sturdiness to the structure as a whole as will be well understood.-

The grate bar unit provided by. my inven- 7 tion comprisestwo half-sections of. substantially. identicalsize and's'hape and only one of these sections will be discribed' in detail.

Referring particularlyto Figs. 1 and 2, each grate bar section consists of a flat body portion 16 having therein the usual diagonally-arranged grate openings 17. This body portion is, preferably, of sufficient lengthto extend from the side wall 11 to the center of the support bar 14 so that the two half sections in assembled position (Fig. 2) meet in substantially end-wise abutting relation, thereby forming' in each grate bar unit (Fig. 1) a substantially continuous, uniform grate bar surface. I I One of the important features of myflinvention has to do with, the manner ofsecurely mounting each half-grate bar section upon the pallet, and thepreferred form ofstruc turewhich I have chosen to i'llustrate'that feature of 'my invention will now be described. The side walls 11 of the pallet are each provided throughout their length, along theirinner surface, with a horizontal ledge or shoulder 18, adapted to support the ends 16 of'the grate bar body in horizontallyaligned position. The underside of the grate bar body 16 at its mid-portion is provided with an integral, depending rib 19' whichextends'from flush with the innerend 16 of the half grate bar section to near, but spaced from its other or side wall seated end 16?. The -so-'ca'lled inward end l9 jof this rib is thickened laterally'to provide a strengthened head-like portion which is notched inwardly in the direction of the length of such rib, as at 20, to give thatend of the grate bar section a jaw shape formation. V I

7 Three grate bar units (Fig. l) are, preferably, mounted upon each pallet with the sections of each unit cooperating withone of the support bars '14. Inassembling each body.

its respective support bar 14 is received in the notch 20 (Fig. 2) so as to be interlockingly embraced by the jaw-formation provided by such notch thereby preventing vertical displacement of that endof the-section from the support bar 14 and the: pallet. When the two sections are so mounted in end-wise abutting relation (Fig. 2), tipping, tilting of the mid-portions (inward ends 16" of the sections) of the grate bar unit is prevented even though there mightbe slight play between the notches 20 and the respective grate bar 14:. The outward endsIG -of the grate bar which are seated upon the side wall ledges 18 are confined against vertical displacement by the side-wall-carried pins 21 engaging suitable depressions 22 in the upper surface of the grate bar body. v a

From the foregoing, it is obvious that each grate bar section, and the grate bar unit as a whole,-is securely locked tothe pallet against vertical displacement in anyposition which the pallet may assume on its conveyor structure.

. It is also highly desirable that each of the grate bar sections be maintained in a substantially predetermined lateralposition with respect to the pallets and each other so that the grate bar units will all'be maintained in the proper position for presenting a substantially continuous, uniform grate bar surface over the bottom of the pallet. To that end,I employ at the inward or jaw end 16 of each i of the sections, depending, integral lugs 23. i

These lugs, on each section, are disposed on opposite sides of the rib 19 near its j aw-end and adjacent the side edges of'the gratebar Furthermore, these lugs are so positioned that whe'nthe section is mounted upon the pallet, said lugs lie close to the adjacent transverse and intermediatebars 12, 13 (or the intermediate bars 13 alone, as the case may be) cooperating therewi-th to prevent lateraldisplacement of the sections with respect to the pallet. This arrangement in conjunction with the end-wise abutting relation between the sections of eachunit, insures that the sections and units will all be held or locked in a substantially fixed position against relative'vertical and lateral displacement. v 1

Theadvantages afforded by my invention will bewell appreciated from the foregoing.

While I have shown only one form of my invention, it will be understood that other changes in details and arrangement of parts may be made without departing from the spirit and scope of my invention as defined by the claims which follow.

I claim:

' 1. In structure of the class described, a support having sides of substantial depth and thickness, spaced cross bars of substantial depth and thickness extending in parallel relation between said sides, inverted U-shaped bars extending transversely between and joined to the mid-portions of said cross bars, so that the horizontal portions of said U- shaped bars are disposed substantially in alignment with the upper surfaces of said cross barEa d a grate bar unit consistihg of two similar se ctions adapted to be disposed in end-to-end relationieaeh said sections having one end jaw-shaped to embrace the horizontal leg of the respective of said U-bars so that in the assembled position ofsaid sections said horizontal leg is surrounded by said grate bar unit, depending lugs adjacent the jaw-shaped end of each said section at the side of each section co-acting with the adjacent of said cross members, and means for supporting and detachably securing the end of each said section opposite its jaw end.

2. In structure of the class described, a support having side members, spaced cross bars integral with and extending in parallel relation between said side members, transverse bars of inverted U-shape extending between and detachably joined to the midportion of said cross-bars, dividing said support into a plurality of grate bar supporting sections, 1 a grate bar unit adapted to be mounted upon said support, each of which units comprise a pair of similar sections adapted to be mounted in end-to-end relation, each of said sections having at one end a j awadapted to embrace the respective transverse bar so that in the assembly of said grate bar unit saidtransverse bar is surrounded by said unit, the other end of each said section being adapted to seat upon said support side, and means carried by said support and detachably engaging each grate bar unit to removably lock said unit in place.

3. In structure of the class described, a support having side members, space-d cross bars extending inparallel relation between said side members, inverted U -shaped bars having relatively thin horizontal web portions extending transversely between said cross bars with their depending U-legs detachably joined to the mid-portions of said cross bars, a grate bar unit consisting of a pair of similar sections each of a width approximating the distance between said cross bars and of a length approximating the distance between said U-shaped bars and said side members, and means for securing each said section to said support which comprises a depending jaw element at one end of each section adapt-- ed to embrace the horizontal web of each of said U-bars so that the grate bar unit in its assembled position substantially surrounds said horizontal web portion of the U-bar, a seat formed upon each said side member to recieve the end of each said section opposite said jaw element, and means carried by each of said side members for releasably securing in place the end of said section seated thereon,

and means carried by each said section and cooperating with said cross bars to prevent lateral displacement of each said section.

4. A grate bar unit for structure of the character described which comprises a pair of sections each having a body portion of generally rectangular shape, an integral centrally disposed rib depending a substantial distance from the underside of said body and extending from one end of the body to near but spaced from its other end, the end of said rib at said one end of the body being notched in the direction of its length to give such end a jaw-shape, and integral lugs depending from said body on the opposite sides of said rib and adjacent said jaw-shaped portion and the side edges of said body.

5. A grate bar unit for structure of the character described which comprises a pair of sections each having a body portion of generally rectangular shape, a centrally disposed rib depending from the underside of said body and extending from one end of the body to near but spaced from its other end, the end of said rib at said one end of the body being thickened laterally to provide a head which head is notched inwardly throughout its width in the direction of the length of said body to give such rib end a sturdy j aw-formation for interlock engagement with a supporting surface, and lugs depending from said body on the opposite sides of said rib and adjacent said head and the side edges of said body.

In testimony whereof, I have subscribed my name.

THOMAS H. BENNETT. 

